Background information about the wind action model of CENELEC EN 50341-1 (2012) and associated expected reliability of electrical overhead lines

The paper focuses on the origins of the wind action model of the CENELEC standard dedicated to the design of electrical overhead lines (EOL). One of the main purposes is to conclude on the full consistence of the CENELEC model with the Eurocode model proposed in EN 1991-1-4 (2005). A successful comparison with experimental wind results is given for a practical validation. A complete calculation of the reliability index regarding design wind loads applied to suspension towers is detailed. When the CENELEC minimum reference reliability level is used in the EOL design, it is shown that the theoretical yearly probability of failure is of at least 10−4 for only a handful of towers per line, which may be charged at their limit conditions. Even if the CENELEC model deals with stationary wind events as winter storms, the resistance of EOL regarding other high-intensity localized wind events like tornadoes or downbursts is also discussed. This background document is written to give an overall understanding of the CENELEC wind load model to EOL engineers.